If you saw a hippo on campus, you would remember it. But, would you expect that seeing such a pachyderm roaming on a university would alter the expression of your DNA? A recent study found that rats placed in an environment that tested their memory had alterations to their DNA, or epigenetic changes.

For a long while, we have generally known that neurons within the hippocampus of our brains are responsible for memory. The current model for memory storage is due to the plasticity of neuronal connections, but researchers have recently found that it also involves active changes at the genetic level. These changes come from external factors and are linked to retaining long-term memories, which has implications in stress-related learning and memory disorders.